It appears that another tethering app snuck has just recently snuck its way into the App Store. QuasiDisk is a $1.99 app that is designed to allow users to quickly and easily transfer files to and from their iOS devices; but the interesting part is what is hidden in the app.
QuasiDisk is given the ability to tether a computer to your iPhone via a proxy, thus allowing you to share your iPhone’s 3G data connection with your computer. A while back there was a similar app called iTether which basically brought tethering to the iPhone and didn’t hide it. The app obviously got pulled from the App Store but people were able to enjoy tethering for the tome being.
Apple is usually pretty quick to pull these types of apps, so you might want to jump on this app if you have a use for tethering without a carrier plan.